1. Technical Field
Inflatable medical devices, sheaths, and methods for making and using the same are disclosed. More narrowly, medical balloons, such as those used for dilatation, are disclosed, as is a sheath for use with a medical balloon.
2. Description of Related Art
Inflatable structures, such as balloons, are widely used in medical procedures. A balloon is inserted, typically on the end of a catheter, until the balloon reaches the area of interest. Adding pressure to the balloon causes the balloon to inflate. In one variation of use, the balloon creates a space inside the body when the balloon inflates.
Balloons may be used in the heart valves, including during Balloon Aortic Valvuloplasty (BAV) and Transcatheter Aortic Valve Implantation (TAVI). The balloons can be used to open a stenosed aortic valve. A stenosed valve may have hard calcific lesions which may tend to tear or puncture a balloon. Additionally, a precise inflated balloon diameter may be desired for increased safety and control.
The high fluid pressures exerted by the heart, combined with the normal pulsation of the opening and closing valves, pose a very dynamic environment for balloon angioplasty. When the balloon is inflated across the valve, the forces tend to squeeze the balloon and create a phenomenon called “ejection,” which causes the balloon to slip out of the valve. The clinician then has to deflate the balloon, reposition it, and re-inflate it, which can prolong the procedure. The inability to dilate the valve properly can also lead to a failed procedure, and lead to alternate, potentially less desirable treatment regimes.
Accordingly, a need is identified for a device to solve the ejection problem. The device would be able to be anchored during inflation, such that valve fluctuations do not eject the balloon from the valve. The device would also be adapted to use perfusion to allow blood flow through the inflated balloon, which provides the added benefit of allowing the blood to circulate normally during longer inflation cycles.